Umbrella



FIG. 1 is a perspective view of an umbrella showing our new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a left side elevational view thereof, the right side elevational view being symmetrical; and,

FIG. 5 is a top plan view thereof.

The surface(s) or portion(s) of the article not shown in the drawing or described in the specification form(s) no part of the claimed design.

The broken line showing of environment in FIGS. 1-4 is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for the umbrella, as shown and described. 